2003 Chevy Tahoe P0161

[Ratazc]

I got a P0161 code over two weeks ago. Reading other posts they said to basically replace the O2 sensor and better yet to replace all four sensors. What I did was just swap the O2 sensors from bank 1 to bank 2 and cleared the code. I figured that the code would change to P0141 if the sensor was bad. Well P0161 came up again (over two weeks later). If it was an open or short, I would think the code would have showed way before two weeks. Suggestions?

Thanks,
Ron

[j cAT]

Originally Posted by Ratazc

I got a P0161 code over two weeks ago. Reading other posts they said to basically replace the O2 sensor and better yet to replace all four sensors. What I did was just swap the O2 sensors from bank 1 to bank 2 and cleared the code. I figured that the code would change to P0141 if the sensor was bad. Well P0161 came up again (over two weeks later). If it was an open or short, I would think the code would have showed way before two weeks. Suggestions?

Thanks,
Ron

so you swaped the O2 sensor and 2 weeks later the 161 code returned ?

my guess is bad wiring or connector. make sure the wires and connector are good ..check all grounds / remove and clean..

also check the PCM connectors for corroded pins. intermittent issue !

bank 2 sensor 2..passenger side downstream sensor.

[Ratazc]

The engine light went off by itself ... I think you are right ... intermittent issue

Originally Posted by j cAT

so you swaped the O2 sensor and 2 weeks later the 161 code returned ?

my guess is bad wiring or connector. make sure the wires and connector are good ..check all grounds / remove and clean..

also check the PCM connectors for corroded pins. intermittent issue !

bank 2 sensor 2..passenger side downstream sensor.

[autojoe]

wrong 02.....wrong bank.....this code does not relate to the fuel control 02 which is the pre cat 02 sensor......it relates to the post cat 02 sensor heater bank 2 sensor 2 which is the bank opposite cylinder 1 and post cat 02 heater.bank 2 sensor 2.did not heat the sensor during startup.check for battery voltage at 02 heater (br-pk) wire if good check (bk) heater ground wire.if both power and ground are good then replace sensor.what size engine?

[SammerSin]

Is this a lot of miles for a 2003 chevy tahoe and 1999 expedition?

[j cAT]

Originally Posted by autojoe

wrong 02.....wrong bank.....this code does not relate to the fuel control 02 which is the pre cat 02 sensor......it relates to the post cat 02 sensor heater bank 2 sensor 2 which is the bank opposite cylinder 1 and post cat 02 heater.bank 2 sensor 2.did not heat the sensor during startup.check for battery voltage at 02 heater (br-pk) wire if good check (bk) heater ground wire.if both power and ground are good then replace sensor.what size engine?

swaping O2 sensors is a sure way to test the O2 AS THE PROBLEM.

with intermittent issue like this you need to do this type of troubleshooting.

he never said anything about fuel management .

this code still should be fixed even though, it is only performing cat converter monitoring performance.

this code will throw if the O2 voltage does not swing properly..could be heater feed connections or the pcm connections, wire damage, connectors...